Wiper device for drill pipe



Oct. 15, 1957 R. PAISO 2,809,387

- WIPER' DEVICE FOR DRILL PIPE I Filed Sept. 16. 1954 H0001. PH E2150,

1 N V EN TOR.

ATTOPNEY.

United WIPER DEVICE FGR DRILL PIPE Application September 16, 1954, Serial No. 456,481

2 Claims. (Cl. 15-219) This invention relates to improved devices for use during the drilling of wells for the purpose of removing drilling muds, fluids, and foreign matter from drill pipe, tubing, and the like, being withdrawn from a well.

During the drilling of an oil well, drilling fluids are employed for the purpose of removing cuttings from the Well hole and the external surfaces of the drill pipe, couplings, collars, etc. become dirty and when the drill string is being withdrawn from the well, the mud, cuttings and other fluids found in the well hole adhere to the external surfaces of the drill pipe and make the handling of the drill pipe sections a diflicult and dirty job. In order to remove or wipe the external surfaces of the drill pipe as it is being pulled out of the well hole, numerous wipers have been employed heretofore. Most prior wipers either consist of a single disc of rubber-like composition pro vided with a central aperture and one or more radial cuts leading away from such aperture so as to permit the lips of the wiper around the aperture to give way for conplings, protectors, and the like or such single disc of rubber-like composition is provided with a head around the central aperture as well as radial cuts. in some instances, two spaced Wipers are employed as, for example, in Paten: No. 2,514, 817. However, none of these wipers have actually completely encircled a drill pipe and collars, since the radial cuts formed in the Wipers open and separate permitting large quantities of mud and foreign matter to remain on the unwiped areas of the drill pipe.

The present invention is directed to an improved economical wiper for drill pipe and tubing, and is characterized by the utilization of a plurality of relatively thin disc-like central elements in superimposed relation, each being of substantially uniform thickness with surfaces which are in substantial contact with adjacent discs but are capable of moving with respect thereto. This stack of superimposed, thin, flexible disc portions is integral with a common outer rim portion, the rim portion being held in position by a suitable lid or housing attached to the casing, casing head or other structure within or on the drilling floor.

it will be evident that the wiper of the present invention presents a plurality of Wiping lips. Since each of the central disc portions is thin, it is very flexible. In accordance with the present invention, described in detail hereafter, a certain relationship exists between the unrestrained radial dimension of each flexible central disc portion and its thickness, whereby most effective and thorough wiping action and removal of mud and debris from drill pipe, couplings, collars, etc., is attained in practice.

It is an obiect of the present invention, therefore, to disclose and provide an improved, simple, and efficient wiping element for use on drill pipe and tubing.

A further object of this invention is to disclose and provide a circular, substantially flat-sided wiper disc having a central portion composed of a plurality of flexible, superimposed, thin disc portions and a single, common {ates 5 3H1 Ft ce outer rim portion integral with the plurality of disc portions.

These and various other objects and advantages will become apparent to those skilled in the art from the following detailed description of an exemplary form of the invention, reference being had to the accompanying drawings for the purpose of facilitating description.

In the drawings:

Fig. 1 is a perspective three-quarter top View of a wiping disc made in accordance with the present invention.

Fig. 2 is an enlarged longitudinal section of one-half of a Wiping element made in accordance with the present invention, a portion of said element being shown in wiping or distorted position, in dash lines.

As indicated in Fig. 1, the entire device is preferably circular and provided with substantially flat upper and lower surfaces. In general, it consists of an outer rim portion 10 and a central portion 11 composed of a plurality of flexible, superimposed disc portions. An axial aperture 12 extends through the stack of superimposed disc portions.

As best shown in Fig. 2, the central portion 11 comprises a stack of relatively thin, flexible disc portions such as 15, 16, 17, 18, 19, and 20-24. In actual practice, it has been found to use no less than four and preferably six or even ten such thin central disc portions in order to obtain most effective wiping action and prolonged life. These disc portions 15-24 are made of any suitable rubber-like composition, the type of composition employed depending somewhat upon the character of the drilling mud being used. In some instances, water-borne or aqueous mud suspensions are employed Whereas in other instances, oil based drilling muds are used; the type of rubber composition chosen should be most resistant to the character of fluids employed in the well.

It will be noted that each of the central disc portions is of substantially uniform thickness and provided with flat, parallel surfaces. The surface 25 of disc 15 is unconnected to and free to move with respect to the surface 26 of disc 16. The external surface of disc portion 15 may be provided with a series of concentric lines or beads such as 30, 31, and the like, so as to permit an operator to cut out an axial aperture through the entire stack of discs, the diameter of such aperture being slightly less than the external diameter of the drill pipe or tubing on which the Wiping device is to be employed. For example, the aperture 12 illustrated may be designed to accommodate the smallest size of drill pipe or tubing whereas the bead 30 may indicate the largest diameter of aperture which can be formed in the device to accommodate the largest size of drill pipe.

It will be noted that the rim 10 is common to and integral with all of the centrally disposed disc portions 15-24. If desired, the outer rim portion 10 may contain a circularly arranged metallic rod or cable 33 to reinforce such rim. Since each of the disc portions 15-24 is integral with the rim 10, the resulting one-piece device is extremely sturdy and stable.

in addition to the central aperture 12 extending through all of the flexible disc portions 15-24, additional apertures such as the passageway 36 may be provided. When the device is in actual use and is suitably held within a cage which restrains upward movement of the device by engaging the rim portion 10, and a drill pipe is being pulled out of the hole through the aperture 12 (or other suitably sized aperture formed in the central disc portions), these flexible disc portions will flex upwardly as indicated by the dash lines, thereby presenting a plurality of wiping edges such as the edges 15, 16', and the like, which Wipe or scrape all of the mud, fluid, debris, oil, etc. off the drill pipe, tubing, collars, couplings, etc.

The material thus scraped off the drill pipe .is.not..permitted to remain between adjacent flexible disc portions but instead can drain off through the auxiliary apertures =such as136 which are displaced from I the. axial center of the device.

One method of manufacturing thedevice disclose-d *hereinabove comprises taking "sheets of rubber stock, such sheets having a diameter equivalent to the overall diameter of 'the'wiping unit to be-builtand separating the central portions of such sheets with discs of spacing material to which the rubber will not adhere during curing. These sheets of parting material may 'consist I of-a cellulose derivative, waxed paper; oiled'paper 'orthe like. The diameter of the parting discs so employedis correlated to the thickness of'the iridividual*sheets;. it being understood that the central "portion'ofeach of such sheets will form theflexible'disc portion of thedevice. It has been foun'ddesirable' to useiparting discs 'ofsuch 'size that even when the largest diameteridrilljpipetis employedfthe free radial dimension of a'fiexible, cen- "trally'disposed disc portion will be not less than fifteen times the thickness of. such discportion.

By referring to Fig. '2, it will be notedfthat'fthe surfaces and 26 of the adjoining discs" 15 and'16 are free, i.'e., they are parted along a-line whose outer. terminus is indicated at37. r'lhe. radial distance between point 37 and the head (indicating the largest axial diameter of the working or Wiping aperture) should be not less than fifteen times the thickness of each of the discs.15 and 16. In actual practice, a ratio ofabout twenty to one has been found very effective.

After the stack of sheets, with central portions properly .separated from each other by parting vdiscs,:has been assembled in a curing mold, the entire stack may be cured, the moldbeing preferably suitably designedto minimize plastic flow during curings. In-this manner, each of the centrally disposed, fiexible discs is an integral part of the rim portion, .the'unpartedsheets curing into a solid mass at the rim. Thestack of-sheets, so cured, may then be suitably perforated to form the axialand auxiliary apertures; in a modified; method: each sheet may be provided with an aperture-orapertures before such sheets are stackedinamold, suitable pins or bosses-of the molds extending through'the apertures, .the parting sheets being annular.

When it is desired/couse;-a:reinforcin g inthe rimxportion, the wiperunit may .be built in two.halves,-eachl-half being provided witha parting faceindicated by dash. lines at 38 and with suitable registry ridges and grooves or pins and depressions .as .indicated "at 39. These two halves can then .be cured together With-'an intervening reinforcing .ring such as 33.

It may be noted thatthe external surfaces'of I the completed device may have a pluralityof inwardly extending, stiifenin g ridges 40 formed therein for the purpose of resisting excessivede'flection of the outer flexible central disc portions.

it may further be noted that additional'rubber com position may be used in forming theexternal rim 10. Sheets of different thicknesses and differing in composition may be used; for example, the' outer sheets such as 15 and 24 may be of harder rubber stockthanthe inner Sheets.

4 As previouslyv indicated, rubber .compositions of different types may be employed; rubber compositions having a short hardness of between about 40 and 60 have been found eminently suited for use in the flexible, centrally disposed disc portions. Moreover, it is not necessary that the external rim portion be reinforced since in some instances, adequate strength or hardness may be imparted-toth'e rim by variation in the composition employed.

All changes and modifications. coming'within the scope of the appended claims are'embraced thereby.

I claim:

1. A- device for cleaning drilling mud, *liquids and debris from drill pipe:andtubingwbei-ng withdrawn from a well hole, comprising: a circular, substantially flatsided wiper disc comprising a central portion composed of a plurality of flexible, superimposed disc portions of rubber-like composition, each ofsaid disc portions being of uniform thickness-and providedwith flat surfacesfthe surfaces of adjacent disc portions being unconnected and free to move in sliding contactwith respect toeach other;

an axial aperture'of virtually uniform diameter'e'xtendi-ng through said superimposed disc portions, and an outer rim portion common to and integral With all of said plurality of disc portions, the surfaces of said disc portions being unconnected to adjacent disc'portionsfor a radial distance from the'axial aperture'of not less than fifteen-times the thickness of'a disc portion and an offset 'draini passageway extending through'the superimposed posed of'a rubber-like composition and'having a central 0 portion composed of not less than four thin disc portions I in superimposed relation,'each of said'disc portions being a of uniformthickness and provided with'virtually smooth,

plane, parallel surfaces, the surfaces of said disc portions being unconnected to and in slida'ble contact with adjacent disc portions for a radial distance of not less than fifteen times the thickness of a 'disc portion; an axial aperture of virtually uniform diameter extending through said superimposed disc portions and adapted to receive drill pipe;-outward edges of said disc portions merging and being bonded together to form a one-piece rim portion common to and integral with saidrplurality of disc portions, and a metallic circularly arranged'rei-nforcing embeddedin said portion.

References Cited in'the fileTSf' this 'patent UNITED STATES PATENTS 

